easyexcel 导出excel文件

easyexcel 引入：

        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-collections4</artifactId>
            <version>4.4</version>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>easyexcel</artifactId>
            <version>2.2.3</version>
        </dependency>

MAIN：

import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.ExcelWriter;
import com.alibaba.excel.annotation.ExcelIgnore;
import com.alibaba.excel.annotation.ExcelProperty;
import com.alibaba.excel.annotation.format.DateTimeFormat;
import com.alibaba.excel.annotation.format.NumberFormat;
import com.alibaba.excel.write.metadata.WriteSheet;
import com.google.common.collect.Lists;
import java.math.BigDecimal;
import java.util.Date;
import java.util.List;
import lombok.Data;

/**
 * 类${file_name}的实现描述：TODO 类实现描述
 *
 * @Author: za-qishaohui
 * @Date: 2021/11/22 15:40
 */
public class WriteTest {

  private static List<DemoData> data() {
    List<DemoData> list = Lists.newArrayList();
    for (int i = 0; i < 10; i++) {
      DemoData data = new DemoData();
      data.setString("字符串" + i);
      data.setDate(new Date());
      data.setDoubleData(0.5678);
      data.setNumData(new BigDecimal("56.01234"));
      list.add(data);
    }
    return list;
  }

  @Data
  public static class DemoData {

    @ExcelProperty("字符串标题")
    private String string;
    @ExcelProperty("日期标题")
    @DateTimeFormat("yyyy-MM-dd")
    private Date date;
    @ExcelProperty("数字标题1")
    @NumberFormat("#.##%")
    private Double doubleData;

    @ExcelProperty("数字标题2")
    @NumberFormat("#.##")
    private BigDecimal numData;
    /**
     * 忽略这个字段
     */
    @ExcelIgnore
    private String ignore;
  }

  /**
   * 最简单的写
   * <p>1. 创建excel对应的实体对象 参照{@link DemoData}
   * <p>2. 直接写即可
   */
  public static void main(String[] args) {
    // 写法1
    String fileName = TestFileUtil.getPath() + "simpleWrite" + System.currentTimeMillis() + ".xlsx";
    System.out.println(fileName);
    // 这里 需要指定写用哪个class去写，然后写到第一个sheet，名字为模板 然后文件流会自动关闭
    // 如果这里想使用03 则 传入excelType参数即可
    EasyExcel.write(fileName, DemoData.class).sheet("模板").doWrite(data());

    // 写法2
    fileName = TestFileUtil.getPath() + "simpleWrite" + System.currentTimeMillis() + ".xlsx";
    System.out.println(fileName);
    // 这里 需要指定写用哪个class去写
    ExcelWriter excelWriter = EasyExcel.write(fileName, DemoData.class).build();
    WriteSheet writeSheet = EasyExcel.writerSheet("模板").build();
    excelWriter.write(data(), writeSheet);
    // 千万别忘记finish 会帮忙关闭流
    excelWriter.finish();
  }
}

工具类：

import java.io.File;
import java.io.InputStream;

public class TestFileUtil {


    public static InputStream getResourcesFileInputStream(String fileName) {
        return Thread.currentThread().getContextClassLoader().getResourceAsStream("" + fileName);
    }

    public static String getPath() {
        return TestFileUtil.class.getResource("/").getPath();
    }

    public static File createNewFile(String pathName) {
        File file = new File(getPath() + pathName);
        if (file.exists()) {
            file.delete();
        } else {
            if (!file.getParentFile().exists()) {
                file.getParentFile().mkdirs();
            }
        }
        return file;
    }

    public static File readFile(String pathName) {
        return new File(getPath() + pathName);
    }

    public static File readUserHomeFile(String pathName) {
        return new File(System.getProperty("user.home") + File.separator + pathName);
    }
}